1. Field of the Invention
The invention relates to a fragrance-containing preparation which, when in use, gives off fragrances into the environment, meaning that it can be used as an air freshener. For the purposes of the invention, air fresheners are products which vaporize fragrances even at room temperature (without additional energy input) and thus perfume the surrounding air.
2. Discussion of the Background
Liquid air fresheners are known (e.g. EP-A 194 017 (U.S. Pat. No. 4,663,081), and 536 444) but, because there is a danger they may leak, they require expensive packaging and careful handling during use. There have thus already been attempts in the past to overcome these disadvantages by using air fresheners in the form of soft gels or pastes of relatively high viscosity (e.g. U.S. Pat. No. 5,324,490). Such products are normally prepared by mixing a perfume oil emulsion and a viscosity-increasing component. Gel-like or paste-like air fresheners do, however, need to satisfy many requirements.
The viscosity-increasing component should be effective in as small an amount as possible, be able to be stirred into the perfume oil emulsion at room temperature, impede evaporation of the perfume oil components as little as possible and, above all, permit as linear an evaporation of the individual perfume oil components as possible, that is, the composition of the evaporating fragrances should be as constant as possible.
The air fresheners themselves should not melt up to temperatures of 60.degree. C.; in addition, they should not have a tendency towards uncontrolled migration of the aqueous phase and definitely not towards synaeresis (even upon cooling); thus, no clearly visible liquid should separate out on the air freshener. Volume shrinkage during use is accepted or even desired because it indicates the reduction in the life of the air fresheners.
No air fresheners which satsify all of the stated requirements are known to date. The object of the invention was thus to provide such improved air fresheners.